81 lines
1.2 KiB
Markdown
81 lines
1.2 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244ad
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title: Decrement a Number with JavaScript
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cM2KeS2'
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forumTopicId: 17558
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dashedName: decrement-a-number-with-javascript
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---
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# --description--
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You can easily <dfn>decrement</dfn> or decrease a variable by one with the `--` operator.
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```js
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i--;
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```
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is the equivalent of
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```js
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i = i - 1;
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```
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**Note:** The entire line becomes `i--;`, eliminating the need for the equal sign.
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# --instructions--
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Change the code to use the `--` operator on `myVar`.
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# --hints--
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`myVar` should equal `10`.
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```js
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assert(myVar === 10);
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```
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`myVar = myVar - 1;` should be changed.
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```js
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assert(
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/var\s*myVar\s*=\s*11;\s*\/*.*\s*([-]{2}\s*myVar|myVar\s*[-]{2});/.test(code)
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);
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```
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You should use the `--` operator on `myVar`.
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```js
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assert(/[-]{2}\s*myVar|myVar\s*[-]{2}/.test(code));
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```
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You should not change code above the specified comment.
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```js
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assert(/var myVar = 11;/.test(code));
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```
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# --seed--
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## --after-user-code--
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```js
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(function(z){return 'myVar = ' + z;})(myVar);
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```
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## --seed-contents--
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```js
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var myVar = 11;
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// Only change code below this line
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myVar = myVar - 1;
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```
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# --solutions--
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```js
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var myVar = 11;
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myVar--;
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```
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